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Rhodococcus is a pathogen that is known to cause infections in animals and humans, mainly in cases of immunocompromised patients. A case of a pediatric cancer patient suffering from a bloodstream infection caused by Rhodococcus corynebacterioides was described in this work. Gram positive rods were isolated from blood cultures. The target bacterium was identified using a combination of biochemical tests, the MALDI-TOF mass spectrometry technique, and the analysis of the 16S rRNA sequence. Moreover, an antimicrobial susceptibility test was performed using the E-test. The isolated bacterium was identified as R. corynebacterioides. The 3-year-old patient was successfully treated with vancomycin and meropenem. This is the first published report of R. corynebacterioides in a pediatric patient diagnosed with retinoblastoma that developed a bloodstream infection. R. corynebacterioides should be considered among the opportunistic infectious agents affecting pediatric cancer patients.
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Bacteriemia , Neoplasias da Retina , Retinoblastoma , Rhodococcus , Sepse , Animais , Humanos , Criança , Pré-Escolar , Retinoblastoma/tratamento farmacológico , RNA Ribossômico 16S/genética , Sepse/diagnóstico , Sepse/tratamento farmacológico , Neoplasias da Retina/complicações , Neoplasias da Retina/tratamento farmacológico , Bacteriemia/diagnóstico , Bacteriemia/tratamento farmacológico , Bacteriemia/microbiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Antibacterianos/uso terapêuticoRESUMO
BACKGROUND: Aging is an independent risk factor for deterioration in functional capacity. Some studies have reported that physical activity (PA) improves functional capacity and physical performance among older adults (OA). Thus the objective of the present study was to assess the longitudinal association between PA and functional and physical performance in non-institutionalized OA. METHODS: A longitudinal analysis using data from the Frailty, Dynapenia and Sarcopenia in Mexican adults (FRADYSMEX, by its Spanish acronym) cohort study was conducted. PA was assessed through the Community Healthy Activities Model Program for Seniors (CHAMPS) instrument. Functionality was measured with the Barthel index and the Lawton and Brody scale, while physical performance was measured with the Short Physical Performance Battery (SPPB). To evaluate the association between the level of PA and physical and functional performance as a continuous variable, a linear regression of mixed effects was performed. To assess PA and dependence in basic activities of the daily life (BADL), instrumental activities of the daily life (IADL), and low physical performance (PP), generalized estimation equation models [to compute odds ratios (OR) and 95% confidence intervals (95%CI)] were computed. RESULTS: Older people who performed moderate to vigorous-intensity PA had a lower risk of dependence in IADL (OR = 0.17; 95%CI: 0.10, 0.80) and lower risk of low PP (OR = 0.18; 95%CI: 0.11, 0.58) compared to those in lower categories of PA. CONCLUSIONS: Older adults living in the community who perform PA of moderate to vigorous intensity have a lower risk of dependence in BADL and IADL and have a lower risk of low PP.
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Fragilidade , Sarcopenia , Idoso , Estudos de Coortes , Exercício Físico , Humanos , Desempenho Físico FuncionalRESUMO
Gram-negative bacteria release nanovesicles, called outer membrane vesicles (OMVs), from their outer membrane. Proteomics has been used to determine their composition. OMVs contain proteins able to elicit an immune response, so they have been proposed as a model to develop acellular vaccines. In this study, OMVs of Brucella suis, B. ovis, B. canis, and B. neotomae were purified and analyzed by SDS-PAGE, transmission electron microscopy and liquid chromatography coupled to mass spectrometry to determine the pan-proteome of these vesicles. In addition, antigenic proteins were detected by western blot with anti-Brucella sera. The in silico analysis of the pan-proteome revealed many homologous proteins, such as Omp16, Omp25, Omp31, SodC, Omp2a, and BhuA. Proteins contained in the vesicles from different Brucella species were detected by anti-Brucella sera. The occurrence of previously described immunogenic proteins derived from OMVs supports the use of these vesicles as candidates to be evaluated as an acellular brucellosis vaccine.
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Antígenos de Bactérias , Proteínas de Bactérias , Brucella , Proteoma , Animais , Antígenos de Bactérias/genética , Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Brucella/genética , Brucella/metabolismo , Brucella canis , Brucella ovis , Brucella suis , Eletroforese em Gel de Poliacrilamida , Proteoma/genética , ProteômicaRESUMO
Extracellular vesicles (EVs) are evaginations of the cytoplasmic membrane, containing nucleic acids, proteins, lipids, enzymes, and toxins. EVs participate in various bacterial physiological processes. Staphylococcus epidermidis interacts and communicates with the host skin. S. epidermidis' EVs may have an essential role in this communication mechanism, modulating the immunological environment. This work aimed to evaluate if S. epidermidis' EVs can modulate cytokine production by keratinocytes in vitro and in vivo using the imiquimod-induced psoriasis murine model. S. epidermidis' EVs were obtained from a commensal strain (ATC12228EVs) and a clinical isolated strain (983EVs). EVs from both origins induced IL-6 expression in HaCaT keratinocyte cultures; nevertheless, 983EVs promoted a higher expression of the pro-inflammatory cytokines VEGF-A, LL37, IL-8, and IL-17F than ATCC12228EVs. Moreover, in vivo imiquimod-induced psoriatic skin treated with ATCC12228EVs reduced the characteristic psoriatic skin features, such as acanthosis and cellular infiltrate, as well as VEGF-A, IL-6, KC, IL-23, IL-17F, IL-36γ, and IL-36R expression in a more efficient manner than 983EVs; however, in contrast, Foxp3 expression did not significantly change, and IL-36 receptor antagonist (IL-36Ra) was found to be increased. Our findings showed a distinctive immunological profile induction that is dependent on the clinical or commensal EV origin in a mice model of skin-like psoriasis. Characteristically, proteomics analysis showed differences in the EVs protein content, dependent on origin of the isolated EVs. Specifically, in ATCC12228EVs, we found the proteins glutamate dehydrogenase, ornithine carbamoyltransferase, arginine deiminase, carbamate kinase, catalase, superoxide dismutase, phenol-soluble ß1/ß2 modulin, and polyglycerol phosphate α-glucosyltransferase, which could be involved in the reduction of lesions in the murine imiquimod-induced psoriasis skin. Our results show that the commensal ATCC12228EVs have a greater protective/attenuating effect on the murine imiquimod-induced psoriasis by inducing IL-36Ra expression in comparison with EVs from a clinical isolate of S. epidermidis.
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Vesículas Extracelulares/metabolismo , Psoríase/terapia , Staphylococcus epidermidis/metabolismo , Animais , Antígenos Ly/metabolismo , Linhagem Celular , Modelos Animais de Doenças , Vesículas Extracelulares/química , Vesículas Extracelulares/transplante , Humanos , Imiquimode/toxicidade , Interleucina-1/antagonistas & inibidores , Interleucina-1/genética , Interleucina-1/metabolismo , Interleucina-17/genética , Interleucina-17/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Camundongos , Infiltração de Neutrófilos , Psoríase/induzido quimicamente , Psoríase/patologia , Pele/metabolismo , Pele/patologia , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Peristomal skin problems are common in ostomy patients and are connected to decreased quality of life and patient independence, as well as increased treatment costs. This study analysed the factors related to peristomal skin changes in order to better define the clinical profile of patients with optimal peristomal skin status. Secondary analysis of data from a nationwide, cross-sectional, retrospective, multicentre study performed in Spain (Uses and Attitudes in Ostomy) (Bueno Cruz et al, 2021) evaluated clinical data, including demographics, preoperative stoma site marking, type of ostomy, device used, frequency of leakage and scores from the Ostomy Skin Tool (OST) and quality of life (QoL) questionnaires. Risk factors for peristomal skin changes were analysed using multivariate analysis, and a predictive nomogram to anticipate optimal peristomal skin status (defined here as discolouration (D), erosion (E), and tissue overgrowth (T) (DET) score of 0) was developed. Some 871 patients with an ostomy using different commercial devices in Spain were evaluated. Multivariate analysis to predict optimal peristomal skin status revealed leakage frequency, patient age, type of ostomy, preoperative siting and type of baseplate used were independent predictors of peristomal skin status. Optimal peristomal skin care should be a treatment goal for nurse specialists in stomal therapy, and its individual influencing variables should be taken into account by nurses specialising in ostomy care.
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Estomia , Estomas Cirúrgicos , Estudos Transversais , Humanos , Qualidade de Vida , Estudos Retrospectivos , Higiene da Pele , Estomas Cirúrgicos/efeitos adversosRESUMO
Pilar sheath acanthoma is an uncommon, benign follicular neoplasm that frequently presents as a solitary lesion. This neoplasm usually appears on the skin around the upper lip of elderly patients. Histopathologically, the neoplasm usually shows a cystic configuration with epithelial lobules resembling to those of the outer root sheath of the hair follicle at the level of the isthmus emanating radially from the cyst wall. We present 3 peculiar cases of a pilar sheath acanthoma showing a plaque-like architecture because the lesions exhibited a horizontal configuration. To our knowledge, there are no previously reported examples of plaque-like pilar sheath acanthoma.
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Acantoma/patologia , Neoplasias Cutâneas/patologia , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-IdadeRESUMO
INTRODUCTION: Recently a score (LARS) has been internationally validates that quantifies the anterior resection syndrome (ARS). The objective of this study is to know the incidence and severity of the ARS using LARS and its correlation with selected variables or risk factors. METHODS: All operated patients with anterior resection for rectal cancer between October 2007 and February 2014, with curative intention and at least one year of functionality, were sent a LARS questionnaire. The variables studied were: Age sex, time elapsed since surgery, type of surgical approach, type of anastomosis, derivative ileostomy, postoperative pelvic complication, and radiotherapy regimen. RESULTS: Out of 195 patients, 136 (70%) responded, and 132 responded properly. A total of 47% of the patients presented "severe" LARS and 34% did not develop quantifiable ARS. Quality of life was worse in the highest LARS scores (P=.002). In the univariate analysis, total mesorectal excision, long radiotherapy regimen and derivative stoma were associated to "severe" LARS and the use of a reservoir was associated with minor LARS. In multivariate analysis only the type of resection (P<.001) and the use of a reservoir (P=.002) were individual factors related to LARS. CONCLUSIONS: Half of the operated patients presented high LARS score and only a third did not provide a quantifiable ARS. The overall perception of quality of life was significantly worse in patients with more severe LARS. The absence of the rectum (total mesorectal excision) and the type of anastomosis were the main factors associated with the LARS score.
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Procedimentos Cirúrgicos do Sistema Digestório , Procedimentos Cirúrgicos do Sistema Digestório/efeitos adversos , Humanos , Incidência , Qualidade de Vida , Neoplasias Retais/etiologia , Reto/cirurgiaRESUMO
Biofilm formation on medical and surgical devices is the main virulence factor of Staphylococcus epidermidis. A recent study has shown that norspermidine inhibits and disassembles the biofilm in the wild-type Bacillus subtilis NCBI3610 strain. In this study, the effect of norspermidine on S. epidermidis biofilm formation of clinical or commensal strains was tested. Biofilm producing strains of S. epidermidis were isolated from healthy skin (HS; n = 3), healthy conjunctiva (HC; n = 9) and ocular infection (OI; n = 19). All strains were treated with different concentrations of norspermidine, spermidine, putrescine, and cadaverine (1, 10, 25, 50 and 100 µM), and the biofilm formation was tested on microtiter plate. Besides, cell-free supernatants of S. epidermidis growth at 4 h and 40 h were analyzed by gas chromatography coupled to mass spectrometry (GC-MS) to detect norspermidine. Results showed that norspermidine at 25 µM and 100 µM prevented the biofilm formation in 45.16% (14/31) and 16.13% (5/31), respectively; only in one isolate from OI, norspermidine did not have effect. Other polyamines as spermidine, putrescine and cadaverine did not have effect on the biofilm formation of the strains tested. Norspermidine was also capable to disassemble a biofilm already formed. Norspermidine was detected in the 40 h cell-free supernatant of S. epidermidis by GC-MS. Norspermidine inhibited the biofilm development of S. epidermidis on the surface of contact lens. In this work, it was demonstrated that S. epidermidis produces and releases norspermidine causing an inhibitory effect on biofilm formation. Moreover, this is the first time showing that clinical S. epidermidis strains have different sensitivity to norspermidine, which suggest that the composition and structure of the biofilms is varied. We propose that norspermidine could potentially be used in the pre-treating of medical and surgical devices to inhibit the biofilm formation.
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Antibacterianos/metabolismo , Biofilmes/efeitos dos fármacos , Espermidina/análogos & derivados , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/fisiologia , Biofilmes/crescimento & desenvolvimento , Meios de Cultura/química , Olho/microbiologia , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Pele/microbiologia , Espermidina/metabolismo , Infecções Estafilocócicas/microbiologia , Staphylococcus epidermidis/crescimento & desenvolvimento , Staphylococcus epidermidis/metabolismoRESUMO
Outer membrane vesicles (OMVs) are released from the outer membrane of Gram-negative bacteria. Moreover, Gram-positive bacteria also produce membrane-derived vesicles. As OMVs transport several bacterial components, especially from the cell envelope, their interaction with the host cell, with other bacteria or as immunogens, have been studied intensely. Several functions have been ascribed to OMVs, especially those related to the transport of virulence factors, antigenic protein composition, and development as acellular vaccines. In this work, we review some of the recent findings about OMVs produced by specific pathogenic bacterial species.
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Estruturas da Membrana Celular/fisiologia , Bactérias Gram-Negativas/fisiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Bactérias Gram-Positivas/fisiologia , Animais , Membrana Celular/metabolismo , Membrana Celular/ultraestrutura , Estruturas da Membrana Celular/metabolismo , Estruturas da Membrana Celular/ultraestrutura , Parede Celular/metabolismo , Bactérias Gram-Negativas/metabolismo , Bactérias Gram-Negativas/patogenicidade , Bactérias Gram-Negativas/ultraestrutura , Bactérias Gram-Positivas/metabolismo , Bactérias Gram-Positivas/patogenicidade , Bactérias Gram-Positivas/ultraestrutura , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Fatores de Virulência/metabolismoRESUMO
The effect of acid treatments with HCl and HNO3 on the surface area and surface chemistry of three granular activated carbons was studied. These supports were characterized and the hydrochloric acid treatment leads to the best activated carbon support (AC2-C). The catalytic behavior of Pt, Ru and Fe (1 wt.%) supported on granular activated carbon treated with HCl was tested in the phenylamine continuous catalytic wet air oxidation in a three-phase, high-pressure catalytic reactor over a range of reaction temperatures 130-170ºC and total pressure of 1.0-3.0 MPa at LHSV = 0.4-1 h(-1), whereas the phenylamine concentration range and the catalyst loading were 5-16 mol.m(-3) and 0.5-1.5 g, respectively. Activity as well as conversion varied as a function of the metal, the catalyst preparation method and operation conditions. Higher activities were obtained with Pt incorporated on hydrochloric acid -treated activated carbon by the ion exchange method. In steady state, approximately 98% phenylamine conversion, 77% of TOC and 94% of COD removal, was recorded at 150ºC, 11 mol m(-3) of phenylamine concentration and 1.5 g of catalyst, and the selectivity to non-organic compounds was 78%. Several reaction intermediaries were detected. A Langmuir-Hinshelwood model gave an excellent fit of the kinetic data of phenylamine continuous catalytic wet air oxidation over the catalysts of this work.
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Compostos de Anilina/química , Ácido Clorídrico/química , Metais/química , Ácido Nítrico/química , Poluentes da Água/química , Ar , Catálise , Cinética , OxirreduçãoRESUMO
Adsorption mechanism of diclofenac and isoproturon onto activated carbon has been proposed using Langmuir and Freundlich isotherms. Adsorption capacity and optimum adsorption isotherms were predicted by nonlinear regression method. Different kinetic equations, pseudo-first-order, pseudo-second-order, intraparticle diffusion model and Bangham kinetic model, were applied to study the adsorption kinetics of emerging contaminants on activated carbon in two aqueous matrices.
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Carvão Vegetal/química , Diclofenaco/isolamento & purificação , Compostos de Fenilureia/isolamento & purificação , Poluentes Químicos da Água/isolamento & purificação , Purificação da Água/métodos , Adsorção , Diclofenaco/química , Difusão , Humanos , Cinética , Modelos Moleculares , Compostos de Fenilureia/química , Águas Residuárias/química , Poluentes Químicos da Água/químicaRESUMO
INTRODUCTION: Human brucellosis diagnosis is based on isolation of Brucella spp. from blood or tissue cultures with a positivity rate of 40-70% and serology techniques are used as complementary tools; recently molecular biology diagnostic techniques have been developed intending to optimize the etiological confirmation. AIM: The main objective of this work was to compare the polymerase chain reaction (PCR), against serological diagnostic tests during the clinical follow-up of a family presenting brucellosis. METHODS: Seven family members who lived in the urban area of Mexico City, were monitored using the Rose Bengal test, the agglutination test as well as agglutination with 2 mecapto ethanol, blood cultures and serum PCR for a period of 27 months. The suspected source of infection was fresh goat cheese from a known endemic zone. RESULTS: Brucella melitensis was isolated from the blood cultures of two patients. All of the patients were positive in serological and PCR tests at the beginning of this follow-up. At the end of the study, three patients responded well to the treatment and showed negative results in the serological and PCR tests. While two patients with diabetes mellitus type 2, showed positive results in the serological and PCR tests as well as persistent symptoms. CONCLUSION: Clinical follow-up of patients with brucellosis is of great importance, to properly evaluate the given treatment. In this sense the PCR is a great supporting tool in diagnostic testing.
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Anticorpos Antibacterianos/sangue , Brucella/genética , Brucella/imunologia , Brucelose/diagnóstico , Adulto , Testes de Aglutinação , Brucelose/tratamento farmacológico , Saúde da Família , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Rosa Bengala , Sensibilidade e Especificidade , Adulto JovemRESUMO
BACKGROUND: Prolonged hospitalization due to the COVID-19 pandemic gathered risk factors for developing invasive candidiasis. AIM: To describe Candida spp. isolated from patients with clinical suspicion of COVID treated in a public hospital specialized in COVID-19 during the pandemic, considering the susceptibility profiles and the risk factors related to the species detected in a positive yeast culture. METHODS: From different samples of 33 patients with comorbidities, 42 clinical isolates were identified by VITEKâ MS Plus. Antifungal susceptibility testing was performed using VITEKâ 2 Compact with the AST-YS08 card. RESULTS: The most frequently identified species were C. albicans and C. glabrata, which were also the most common co-infections, Saprochaete capitata, an uncommon yeast was isolated in one patient. 85% of the co-infections were COVID positive and 100% of patients with a co-infection required mechanical ventilation (MV) which has been described as one of the major predisposing factors to candidiasis. Candida species vary in their response to treatment. In this study, 44% of isolates identified as C. glabrata were fluconazole-resistant, which were also immediately susceptible to caspofungin; this profile limits therapeutic options and emphasizes the importance of evaluating the susceptibility profile. CONCLUSIONS: This work highlights the increase in isolation of different Candida species during COVID-19 and the importance of establishing criteria to declare Candida colonization or infection and the correct etiological identification to establish an agent-based antifungal treatment, to reduce the spreading risk of Candida spp. in the hospital environment, mortality, time, and cost of hospitalization.
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BACKGROUND: Many women covered by the Spanish public health system also have an extra private insurance policy for gynecological examinations and routine annual mammography. We retrospectively analyzed the long-term survival rates in these patients when diagnosed with breast cancer. METHODS: We analyzed the survival and prognostic factors in patients diagnosed with breast cancer who were referred to a medical oncology unit for multidisciplinary treatment covered by private health insurance. RESULTS: Between 1994 and 2009, a total of 434 patients with breast tumor were analyzed: 33 in situ and 401 infiltrating. Among the infiltrating carcinomas, 38 were stage IV and 363 were stage I, II, or III. With a median follow-up of 62 months, the 5-year global survival rate was 91%: 97% for stage I, 94% for stage II, and 77% for stage III tumors. In the patients diagnosed by routine mammography, the 5-year survival rate was 96%, compared with 86% in those consulting their gynecologist after breast self-examination or for other symptoms (p=0.0159). Seventy-four percent were treated conservatively and experienced better survival than the 26% who underwent mastectomy (p=0.0024). Patients with disease with positive hormone receptors had a better survival rate (p=0.0264); hormone receptor status was the only independent prognostic factor in the Cox multivariate analysis. Postmenopausal patients who received adjuvant tamoxifen plus exemestane had a better prognosis than those who received tamoxifen alone (p=0.0203). CONCLUSIONS: Long-term survival rate was high in breast cancer patients with extra private insurance coverage. This is probably because disease was diagnosed at an early stage.
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Neoplasias da Mama/mortalidade , Cobertura do Seguro , Recidiva Local de Neoplasia/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/patologia , Neoplasias da Mama/terapia , Terapia Combinada , Feminino , Seguimentos , Humanos , Metástase Linfática , Mamografia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Recidiva Local de Neoplasia/terapia , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
PURPOSE: There are some circumstances in which the descending colon does not reach the pelvis to complete a colorectal anastomosis without tension. Re-establishing intestinal continuity by interposing small bowel as a bridge between the colon and the rectum could be an acceptable surgical alternative. METHODS: We describe the interposition of one or two segments of small bowel as a way of restoring continuity of the colon and rectum in three patients in whom it was not possible to perform a colorectal anastomosis without tension due to ischaemic colon, synchronous cancer or difficulty in accessing the supramesocolic space, respectively. RESULTS: Intestinal continuity was re-established in all patients with no significant morbidity and good intestinal function. CONCLUSION: The interposition of small bowel segments between the colon and the rectum should be considered a valid surgical option when it is not possible to achieve a well-perfused, tension-free pelvic colorectal anastomosis.
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Colo/cirurgia , Intestino Delgado/cirurgia , Reto/cirurgia , Idoso , Anastomose Cirúrgica/métodos , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Humanos , Masculino , Pessoa de Meia-Idade , PressãoRESUMO
Currently, genome editing technologies, such as clustered regularly interspaced short palindromic repeats (CRISPR/Cas9), are predominantly used to model genetic diseases. This genome editing system can correct point or frameshift mutations in risk genes. Here, we analyze and discuss the advantages of genome editing, its current applications, and the feasibility of the CRISPR/Cas9 system in research on psychiatric disorders. These disorders produce cognitive and behavioral alterations and their etiology is associated with polygenetic and environmental factors. CRISPR/Cas9 may reveal the biological mechanisms of psychiatric disorders at a basic research level, translating a suitable clinical approach for use in the diagnosis and treatment of psychiatric disorders. Genetic diagnosis and treatment for these disorders have not yet been fully established in psychiatry due to the limited understanding of their heterogeneity and polygenicity. We discuss the challenges and ethical issues in using CRISPR/Cas9 as a tool for diagnosis or gene therapy.
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Sistemas CRISPR-Cas , Edição de Genes , Humanos , Sistemas CRISPR-Cas/genética , Terapia GenéticaRESUMO
The use of sulfidogenic bioreactors is a biotechnology trend to recover valuable metals such as copper and zinc as sulfide biominerals from mine-impacted waters. In the present work, ZnS nanoparticles were produced using "green" H2S gas generated by a sulfidogenic bioreactor. ZnS nanoparticles were physico-chemically characterized by UV-vis and fluorescence spectroscopy, TEM, XRD and XPS. The experimental results showed spherical-like shape nanoparticles with principal zinc-blende crystalline structure, a semiconductor character with an optical band gap around 3.73 eV, and fluorescence emission in the UV-visible range. In addition, the photocatalytic activity on the degradation of organic dyes in water, as well as bactericidal properties against several bacterial strains, were studied. ZnS nanoparticles were able to degrade methylene blue and rhodamine in water under UV radiation, and also showed high antibacterial activity against different bacterial strains including Escherichia coli and Staphylococcus aureus. The results open the way to obtain valorous ZnS nanoparticles from the use of dissimilatory reduction of sulfate using a sulfidogenic bioreactor.
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Introduction: Tuberculosis (TB) is a bacterial infection caused by Mycobacterium tuberculosis (M.tb). B cells are the central mediator of the humoral response; they are responsible for producing antibodies in addition to mediating other functions. The role of the cellular response during the TB spectrum by B cells is still controversial. Methods: In this study, we evaluated the distribution of the circulating B cell subsets in patients with active and latent TB (ATB and LTB, respectively) and how they respond to stimuli of protein or lipid from M.tb. Results: Here, we show that ATB patients show an immune fingerprinting. However, patients with drug-sensitive- (DS-TB) or drug-resistant- (DR-TB) TB have altered frequencies of circulating B cells. DS-TB and DR-TB display a unique profile characterized by high systemic levels of IFN-γ, IL-10, IgG, IgG/IgM ratio, and total B cells. Moreover, B cells from DR-TB are less efficient in producing IL-10, and both DS-TB and DR-TB produce less IFN-γ in response to M.tb antigens. Conclusion: These results provide new insights into the population dynamics of the cellular immune response by B cells against M.tb and suggest a fingerprinting to characterize the B-cell response on DR-TB.
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Tuberculose Latente , Mycobacterium tuberculosis , Tuberculose , Humanos , Interleucina-10 , Interferon gama/metabolismo , Imunoglobulina GRESUMO
Dysbiosis plays an important role in the development of bacterial infections in the gastric mucosa, particularly Helicobacter pylori. The international guidelines for the treatment of H. pylori infections suggest standard triple therapy (STT). Nevertheless, because of the increasing resistance rates to clarithromycin, metronidazole has been widely considered in several countries. Unfortunately, the non-justified administration of antibiotics induces dysbiosis in the target organ. We characterized the gastric microbiota of patients diagnosed with follicular gastropathy and pangastropathy attributed to H. pylori infection, before and after the administration of STT with metronidazole. Dominant relative abundances of Cutibacterium were observed in pre-treatment patients, whereas H. pylori was observed at <11%, suggesting the multifactor property of the disease. The correlation of Cutibacterium acnes and H. pylori with gastric infectious diseases was also evaluated using quantitative real-time polymerase chain reaction. The dominance of C. acnes over H. pylori was observed in gastritis, gastropathies, and non-significant histological alterations. None of the microorganisms were detected in the intestinal metaplasia. Post-treatment alterations revealed an increase in the relative abundances of Staphylococcus, Pseudomonas, and Klebsiella. Non-H. pylori gastrointestinal bacteria can be associated with the initiation and development of gastric diseases, such as pathobiont C. acnes.
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The outer membrane vesicles (OMVs) from smooth B. melitensis 16 M and a derived rough mutant, VTRM1 strain, were purified and characterized with respect to protein content and induction of immune responses in mice. Proteomic analysis showed 29 proteins present in OMVs from B. melitensis 16 M; some of them are well-known Brucella immunogens such as SOD, GroES, Omp31, Omp25, Omp19, bp26, and Omp16. OMVs from a rough VTRM1 induced significantly higher expression of IL-12, TNFα, and IFNγ genes in bone marrow dendritic cells than OMVs from smooth strain 16 M. Relative to saline control group, mice immunized intramuscularly with rough and smooth OMVs were protected from challenge with virulent strain B. melitensis 16 M just as well as the group immunized with live strain B. melitensis Rev1 (P < 0.005). Additionally, the levels of serum IgG2a increased in mice vaccinated with OMVs from rough strain VTRM1 consistent with the induction of cell-mediated immunity.